espionage

noun

es·​pi·​o·​nage ˈe-spē-ə-ˌnäzh  -ˌnäj 

-nij

Canadian also -ˌnazh;

ˌe-spē-ə-ˈnäzh;

i-ˈspē-ə-nij

: the practice of spying or using spies to obtain information about the plans and activities especially of a foreign government or a competing company

industrial espionage

Synonyms of espionage

• spying

Examples of espionage in a Sentence

He was charged with several counts of espionage.

the acts of espionage on behalf of the Confederacy carried on by Belle Boyd and Rose Greenhow

Recent Examples on the Web

Wind turbines are vulnerable to cyber espionage and cyberattacks, according to De Kleijn. — Sam Birchall, Fortune, 2 Oct. 2026

Together, the recent breaches represent one of the biggest potential espionage hauls since the 2015 hack of the US Office of Personnel Management. — Dan Goodin, ArsTechnica, 1 Oct. 2026

Mehmet Eser | Anadolu | Getty Images How did John Harold Rogers go from a senior Federal Reserve official to an espionage suspect arrested by the FBI? — Alex Harring, CNBC, 30 Sep. 2026

Evan Gershkovich, the Wall Street Journal reporter who was imprisoned in Russia in March 2023 on espionage charges, was released in August 2024 as part of a prisoner swap with the United States. — Scott Nover, Washington Post, 30 Sep. 2026

Word History

Etymology

French espionnage, from Middle French, from espionner to spy, from espion spy, from Old Italian spione, from spia, of Germanic origin; akin to Old High German spehōn to spy — more at spy

First Known Use

1793, in the meaning defined above

Kids Definition

espionage

noun

es·​pi·​o·​nage ˈes-pē-ə-ˌnäzh  -näj 

-ˌnij

: the practice of spying : the use of spies

Legal Definition

espionage

noun

es·​pi·​o·​nage ˈes-pē-ə-ˌnäzh, -ˌnäj, -nij 

: the practice of gathering, transmitting, or losing through gross negligence information relating to the defense of the U.S. with the intent that or with reason to believe that the information will be used to the injury of the U.S. or the advantage of a foreign nation